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Determination of 14 Organophosphorus Pesticide Residues in Mutton by Gel Permeation Chromatography-Gas Chromatography-Mass Spectrometry(GPC-GC-MS)
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作者 Junpeng ZHAO Richard Avoi +2 位作者 Azman Bin Atil@Azmi Jiao CHEN Ling YUN 《Agricultural Biotechnology》 2024年第3期28-30,33,共4页
[Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by ga... [Objectives]This study was conducted to purify mutton samples by gel permeation chromatography(GPC).[Methods]Fourteen organophosphorus pesticide residues in samples were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry(GC-MS)in selective ion scanning mode(SIM).[Results]The organophosphorus pesticide standard solutions showed good linearity in the mass concentration range of 0.1-10.0μg/ml with correlation coefficients(r)not lower than 0.999,and the detection limits(S=3 N)ranged from 0.01 to 0.05 mg/kg.The average recovery values were in the range of 80.2%-99.7%,with relative standard deviations(RSDs,n=3)in the range of 1.8%-6.3%,at the addition levels of 0.5,1.0 and 2.0 mg/kg.[Conclusions]The method is simple,sensitive and accurate,and can be used for the determination of organophosphorus pesticide residues in mutton. 展开更多
关键词 MUTTON Gas chromatography-mass spectrometry gel permeation chromatography ORGANOPHOSPHORUS Pesticide residue
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Separation and purification of deoxynivalenol(DON) mycotoxin from wheat culture using a simple two-step silica gel column chromatography 被引量:7
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作者 ZHAO Xiu-mei LI Rong-jia +5 位作者 ZHOU Chuang ZHANG Jie HE Cheng-hua ZHENG Ya-ting WU Wen-da ZHANG Hai-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第3期694-701,共8页
Deoxynivalenol(DON) is a type B trichothecenes mycotoxin produced by several Fusarium species, often found in foodstuffs for humans and animals. DON is in great demand for the toxicological researches both in vivo a... Deoxynivalenol(DON) is a type B trichothecenes mycotoxin produced by several Fusarium species, often found in foodstuffs for humans and animals. DON is in great demand for the toxicological researches both in vivo and in vitro. In this work, wheat culture was inoculated with a Fusarium graminearum PH-1 strain for DON production. The solvent system for crude extraction was acetonitrile-water(84:16, v/v). A simple two-step silica gel column chromatography was employed to separate the DON mycotoxin from wheat culture, combined with preparative high performance liquid chromatography(preparative HPLC) to purify the compound. The solvent system for the second silica gel column chromatography was methylene chloride-methanol(17:1, v/v), which provided a good elution effect selected on thin layer chromatography(TLC). The target compound was identified by HPLC, and the chemical structure was confirmed by mass spectrometry(MS) and ~1H and ^(13)C nuclear magnetic resonance(NMR) spectroscopy. A total of 433 mg of purified DON was obtained from 1 kg of wheat culture, with a purity of 99.01%. The study had provided an easy-operating and cost-effective method to isolate an expensive compound in a simple way. 展开更多
关键词 deoxynivalenol silica gel column chromatography separation purification
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Determination of Steroid Hormone Residues in Fish Tissues Using Gel Permeation Chromatography and Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry 被引量:3
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作者 LI Peipei YAN Zhongyong +3 位作者 SUN Xiumei CHEN Si CHEN Yin ZHANG Xiaojun 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1171-1177,共7页
A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 s... A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L^(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg^(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg^(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues. 展开更多
关键词 ultra performance liquid chromatography-tandem mass spectrometry anabolic hormone gel permeation chromatography fish tissue
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Separation and Purification of Acetophenones from Cynanchum bengei Decne Root Bark by Combination of Silica Gel and High-speed Counter-current Chromatography 被引量:1
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作者 Huaizhi LI Lingchuan XU +4 位作者 Xiao WANG Qian LIU Jia LI Peng YANG Bingtian YANG 《Medicinal Plant》 2017年第2期8-11,共4页
[Objectives] To develop a method for separation and purification of acetophenones from Cynanchum bengei Decne root bark by combination of silica gel and high-speed counter-current chromatography( HSCCC). [Methods]The ... [Objectives] To develop a method for separation and purification of acetophenones from Cynanchum bengei Decne root bark by combination of silica gel and high-speed counter-current chromatography( HSCCC). [Methods]The crude extract of Cynanchum bengei Decne root bark was separated by silica gel column chromatography,and parts A and B containing acetophenones were obtained. Then,parts A and B were separated by HSCCC with a two-phase solvent system composed of petroleum ether-ethyl acetate-methanol-water( 4∶ 6∶ 4. 5∶ 5. 5 and4∶ 6 ∶ 3 ∶ 7, V/V), respectively. [Results] From 260 mg of part A, four compounds with p-dihydroxybenzene 3. 9 mg(Ⅰ),4-hydroxyacetophenone 17. 1 mg( Ⅱ),2,5-di-hydroxyacetophenone 13. 3 mg(Ⅲ) and 2,4-dihydroxyaceto-phenone 21. 0 mg(Ⅳ) were obtained. And from 300 mg of part B,136 mg of Radix Cynanchi Bungei benzophenone(Ⅴ) was obtained. The purity of compounds determined by HPLC was 97. 0%,96. 6%,99. 2%,99. 7%,99. 5%,respectively. [Conclusions] The established method is simple and efficient. It can be used for separation of acetophenones from Cynanchum bengei Decne root bark and has better practical value,which could provide a reference basis for development and utilization of Cynanchum bengei Decne root bark. 展开更多
关键词 Silica gel column chromatography High-speed COUNTER-CURRENT chromatography(HSCCC) Acetophenones CYNANCHUM bengei Decne root BARK
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Molecular weight determination of a newly synthesized guanidinylated disulfide-containing poly(amido amine) by gel permeation chromatography 被引量:3
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作者 Haonan Xing Mei Lu +4 位作者 Lei Xian Jinmin Zhang Tianzhi Yang Li Yang Pingtian Ding 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2017年第3期292-298,共7页
A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). ... A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). Gel permeation chromatography(GPC) was used to evaluate the molecular weight of synthesized CAR-CBA. Polyethyleneimine(PEI) with molecular weight of 25 kDa was adopted as a reference, and polyethylene glycols(PEG) with different molecular weights were used to establish a standard curve for determining the molecular weight of CAR-CBA. The effects of two critical factors, namely columns and eluents,on the molecular weight measurement of CAR-CBA were investigated to optimize the GPC quantitative method. The results showed that Ultrahydrogel columns(120, 250) and HAc–NaAc(0.5 M, pH 4.5) buffer solution were the optimal column and GPC eluent, respectively.The molecular weight of the synthesized CAR-CBA was analyzed by the optimized GPC method and determined to be 24.66 kDa. 展开更多
关键词 Guanidinylated disulfide-containing poly(amido amine) Synthesis Cationic gene delivery vector Molecular weight determination gel PERMEATION chromatography
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The Development of Gel Media and Columns for Large-Scale Chromatography of Proteins, a Historical Review 被引量:2
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作者 Jan-Christer Janson 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2002年第6期690-695,共6页
The first dedicated protein chromatography media were introduced during the 1950s and 1960s. There was an early awareness of the possibility of using these for production applications within the biopharmaceutical indu... The first dedicated protein chromatography media were introduced during the 1950s and 1960s. There was an early awareness of the possibility of using these for production applications within the biopharmaceutical industry. However, the crucial limitation was the fact that those media that were most compatible with proteins lent themselves less favourably to scaling-up. The problems were primarily physical. Thus the fibrous cellulose media showed bed cracking tendencies and the bead shaped polyacrylamide, dextran, and agarose gel media, then available, were too soft to stand the hydrodynamic forces acting in large columns, leading to bed compaction and increased pressure drop. At the time, the best solution to the latter problem, after a number of intermediary solutions were tried, was the introduction of the stacked column concept in which several short column segments were connected by small bore tubing, thus reducing the force acting on the particles in each bed copartment. However, the ultimate remedy, the introduction of chromatographic matrices that combine the desired features of adequate rigidity, macroporosity, biocompatibility, chemical stability (for CIP and SIP) and derivatizability, did not occur until the middle of the 1980s when adquately cross-linked agarose gel media such as Sepharose Fast Flow were made available. The paper also recognizes the many attempts made during the past 50 years to develop continous chromatography columns. Most of the designs are based on an annular bed or on an array of anularly arranged parallel columns continuously fed with samples in a cyclic manner. The introduction of media and columns for expanded bed adsorption followed a demand for fewer purification steps and shorter process times. In recent years, columns have been introduced that allow packing and repacking without needing to open the column. The review provides an historical account of the developments that have led to the present state-of-the-art both regarding large diameter columns and gel media intended for industrial applications of protein chromatography and also discusses the current trends that point to possible future applications. 展开更多
关键词 chromatography PROTEIN review
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Rapid,simple and stability-indicating determination of polyhexamethylene biguanide in liquid and gel-like dosage forms by liquid chromatography with diode-array detection 被引量:2
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作者 Markus Küsters Soren Beyer +2 位作者 Stephan Kutscher Harald Schlesinger Michael Gerhartz 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第6期408-414,共7页
A rapid and simple method for the determination of potyhexamethylene biguanide (polyhexanide, PHMB) in liquid and gel-like pharmaceutical formulations by means of high performance liquid chromatography coupled to di... A rapid and simple method for the determination of potyhexamethylene biguanide (polyhexanide, PHMB) in liquid and gel-like pharmaceutical formulations by means of high performance liquid chromatography coupled to diode-array detection (HPLC DAD) was devel- oped. Best separation was achieved using a cyanopropyl bonded phase (Agilent Zorbax Eclipse XDB-CN column 4.6mm x 75 mm with particle size of 3.5 μm) as well as gradient elution consisting of acetonitrile/deionized water at a flow rate of 1.0 mL/min. The optimized and applied chromatographic conditions permitted separation of polyhexanide from interacting raatrix with subsequent detection at a wavelength of 235 nm with good sensitivity. The method validation was carried out with regard to the guidelines for analytical procedures demanded by the International Conference on Harmonisation (ICH). Mean recoveries of 102% and 101% for gel-like as well as liquid preparations were obtained. Suitable repeatability as well as intermediate precision could bc achieved with limits of detection ≤0.004 mg/mL for both formulations, equivalent to ≤0.004% PHMB concerning sample preparation. Determination of PHMB was accomplished without tedious sample preparation. Interacting matrix could be eliminated by the chromatographicprocedure with excellent performance of system suitability. All analytical requirements were fulfilled permitting a reliable and precise determination of PHMB in pharmaceuticals. Further- more, the developed method was applied to stability testing of pharmaceutical preparations containing PHMB. 展开更多
关键词 Polyhexamethylene biguanide Polyhexanide Pharmaceuticals High performance liquid chromatography
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Metal cation exchanged silica gel for identification of cationic and nonionic surfactants with preliminary separation by thin layer chromatography
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作者 Mohammacl Ali Khatoon Shumaila 《Journal of Chemistry and Chemical Engineering》 2009年第6期44-48,共5页
Silica gel impregnated with 1% aqueous solutions of different metal cations (Li^+, Mg^2+, Zn^2+, Cu^2+, Co^2+, Ni^2+, Ba^2+and Th^4+) has been used for the analysis of nonionic and cationic surfaetants using... Silica gel impregnated with 1% aqueous solutions of different metal cations (Li^+, Mg^2+, Zn^2+, Cu^2+, Co^2+, Ni^2+, Ba^2+and Th^4+) has been used for the analysis of nonionic and cationic surfaetants using simple aqueous acetone as mobile phase system. Co^2+ was found the most suitable impregnant for the mutual separation of nonionic surfactants (Brij-35 and Brij-57) and cationic from nonionic surfactants (tetmdecyltrimethylammonium bromide and Cween-20). Zinc sulphate impregnation (Zn^2+-silica gel) shows identical chromatographic behavior and these layers are useful to separate nonionic surfactant (Brij-35) from cationic surfaetant (cetylpyridinium chloride). The mutual separation of B J-35 and B J-57 is not influenced by the presence of optical brightener in the sample. 展开更多
关键词 TLC metal cations silica gel SURFACTANTS
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Comparison in vitro permeation of curcumin from topical gels by liquid chromatography tandem mass spectrometry
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作者 SUN Jun HAN Jinzhao +2 位作者 CHENG Yaqin LI Zhen HU Jinhong 《Journal of Medical Colleges of PLA(China)》 CAS 2013年第6期335-344,共10页
Objective: To fred a more effective method of topical transdermal delivery of curcumin. Methods: We prepared curcumin carbopol (CRB) 974P and hydroxypropylcellulose (HPC) gel formulations containing menthol or A... Objective: To fred a more effective method of topical transdermal delivery of curcumin. Methods: We prepared curcumin carbopol (CRB) 974P and hydroxypropylcellulose (HPC) gel formulations containing menthol or Azone as permeation enhancers In this study, negative mode electrospray ionization and a triple quadruple LC/MS/MS instrument operated in multiple reaction mode was used for curcumin detection. The assay was linear over a concentration range of 10 ng/mL to 400 ng/mL for curcumin (average R2 = 0.997 2). Excised nude mouse dorsal side skin was used in an in vitro skirt permeation study performed using the method of Franz. Results: Our results showed that all of the topical gel formulations we developed were free from skin irritation. The percutaneous flux and enhancement ratio of curcumin across nude mouse epidermis were enhanced markedly by the addition of menthol or Azone to both types of gel formulations. We found that the HPC gels containing quantities of Azone showed an enhanced permeation effect as compared to gels containing menthol. In the case of HPC gels containing Azone, the increase in permeability was significant (P〈0.05) as compared to the gels containing menthol. Conclusion: Azone shows a significantly more remarkable permeation effect than menthol. As such, this novel delivery strategy offers significant promise and is worthy of further exploration in attempts to enhance the medicinal application of curcumin 展开更多
关键词 CURCUMIN gel AZONE MENTHOL Permeation HYDROXYPROPYLCELLULOSE
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Molecule‑Level Multiscale Design of Nonflammable Gel Polymer Electrolyte to Build Stable SEI/CEI for Lithium Metal Battery
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作者 Qiqi Sun Zelong Gong +13 位作者 Tao Zhang Jiafeng Li Xianli Zhu Ruixiao Zhu Lingxu Wang Leyuan Ma Xuehui Li Miaofa Yuan Zhiwei Zhang Luyuan Zhang Zhao Qian Longwei Yin Rajeev Ahuja Chengxiang Wang 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期404-423,共20页
The risk of flammability is an unavoidable issue for gel polymer electrolytes(GPEs).Usually,flameretardant solvents are necessary to be used,but most of them would react with anode/cathode easily and cause serious int... The risk of flammability is an unavoidable issue for gel polymer electrolytes(GPEs).Usually,flameretardant solvents are necessary to be used,but most of them would react with anode/cathode easily and cause serious interfacial instability,which is a big challenge for design and application of nonflammable GPEs.Here,a nonflammable GPE(SGPE)is developed by in situ polymerizing trifluoroethyl methacrylate(TFMA)monomers with flame-retardant triethyl phosphate(TEP)solvents and LiTFSI–LiDFOB dual lithium salts.TEP is strongly anchored to PTFMA matrix via polarity interaction between-P=O and-CH_(2)CF_(3).It reduces free TEP molecules,which obviously mitigates interfacial reactions,and enhances flame-retardant performance of TEP surprisingly.Anchored TEP molecules are also inhibited in solvation of Li^(+),leading to anion-dominated solvation sheath,which creates inorganic-rich solid electrolyte interface/cathode electrolyte interface layers.Such coordination structure changes Li^(+)transport from sluggish vehicular to fast structural transport,raising ionic conductivity to 1.03 mS cm^(-1) and transfer number to 0.41 at 30℃.The Li|SGPE|Li cell presents highly reversible Li stripping/plating performance for over 1000 h at 0.1 mA cm^(−2),and 4.2 V LiCoO_(2)|SGPE|Li battery delivers high average specific capacity>120 mAh g^(−1) over 200 cycles.This study paves a new way to make nonflammable GPE that is compatible with Li metal anode. 展开更多
关键词 Anchoring effect Nonflammable gel electrolyte In situ cross-linked Electrode-electrolyte interface Li metal battery
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Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex
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作者 Yan Li Peng Hao +6 位作者 Hongmei Duan Fei Hao Wen Zhao Yudan Gao Zhaoyang Yang Kwok-Fai So Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第10期2923-2937,共15页
The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate ne... The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries. 展开更多
关键词 adult endogenous neurogenesis basic fibroblast growth factor-hyaluronic acid collagen gel cortical remodeling functional recovery migration motor cortex injury neural circuits neural stem cells newborn neurons proliferation
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Gel Filtration Chromatography Combined with Bradford Method for Determination of Total Residual Protein in Ferment Antibiotics 被引量:6
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作者 许明哲 马仕洪 胡昌勤 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第4期262-266,共5页
Aim A novel method has been developed for evaluation of the levels of total residual protein in antibiotics produced by fermentation using gel filtration chromatography (GFC) combined with Bradford assay based on dete... Aim A novel method has been developed for evaluation of the levels of total residual protein in antibiotics produced by fermentation using gel filtration chromatography (GFC) combined with Bradford assay based on determination of residual protein in lincomycin hydrochloride. Methods The chromatographic conditions were SuperdexTM peptide column, 0.01 mol*L-1 phosphate buffer solution as mobile phase, and flow rate of 1 mL·min-1. Five hundred microliters of lincomycin hydrochloride solution (3 g of lincomycin hydrochloride dissolved in 10 mL of mobile phase) was injected into the chromatograph and the eluted solution was collected between 6 min and 14.5 min (protein eluted from column within this period), and the residual content of total protein in the eluted solution was assayed using Bradford assay method. Results The average recovery was more than 90% for bovine serum albumin, the calibration equation for the range of 0-12 μg·mL-1 of protein was y=-0.002 4x2+0.064 2x+0.002 9, r2=0.999 9, RSD=0.1%-0.9%, and the LOD and LOQ were 3 and 10 ng·mL-1 of protein, respectively. Conclusion The novel method for determining the residual protein in ferment antibio-tics is simple, rapid, and precise. 展开更多
关键词 gel filtration chromatography bradford assay residual protein ferment antibiotics lincomycin hydrochloride
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Gel Permeation Chromatography Purification and Gas Chromatography-Mass Spectrometry Detection of Multi-Pesticide Residues in Traditional Chinese Medicine 被引量:2
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作者 Wan-E Zhuang Zhen-Bin Gong 《American Journal of Analytical Chemistry》 2012年第1期24-32,共9页
The measurement of 23 organochlorine, organophosphorus, and pyrethroid pesticides in typical traditional Chinese medicine (TCM), flos lonicerae, was made using gel permeation chromatography (GPC) purification and gas ... The measurement of 23 organochlorine, organophosphorus, and pyrethroid pesticides in typical traditional Chinese medicine (TCM), flos lonicerae, was made using gel permeation chromatography (GPC) purification and gas chroma- tography-mass spectrometry (GC-MS) detection. The pesticides were extracted with ultrasonic device and 5.0 mL mixture of ethyl acetate and cyclohexane (1:1, v/v). Coextractants from sample matrices which may have interfere to the qualitative and quantitative analysis, such as pigments, were removed using GPC purification. Simultaneous full scan and selective ion monitor (scan/SIM) mode for GC-MS was used for qualitative and quantitative analysis, which pro- vided retention time and characteristic fragments ratio for each pesticide so as to positively identify each analyte. Rela- tive standard deviations (RSDs) were within 7.7% (5.0 - 22.5 μg/kg, n = 3). The recoveries of pesticide standards at the spiked concentration of 5.0 - 22.5 μg/kg were between 87.1% and 110.9%. Limits of detection (LODs) for the analytes were 0.16 - 3.2 μg/kg, which could meet the demand of routine analysis and TCM quality control. 展开更多
关键词 Traditional Chinese Medicine Multi-Pesticide RESIDUE Flos Lonicerae gel PERMEATION chromatography Gas chromatography-Mass SPECTROMETRY
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Analysis of residual crosslinking agent content in UV cross-linked poly(ethylene oxide) hydrogels for dermatological application by gas chromatography 被引量:1
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作者 Rachel Shet Hui Wong Mark Ashton Kalliopi Dodou 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第5期307-312,共6页
Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively... Acrylates have been widely used in the synthesis of pharmaceutical polymers. The quantitation of residual acrylate monomers is vital as they are strong irritants and allergens, but after polymerization, are relatively inert, causing no irritation and allergies. Poly(ethylene oxide)(PEO) hydrogels were prepared using pentaerythritol tetra-acrylate(PETRA) as UV crosslinking agent. A simple, accurate, and robust quantitation method was developed based on gas chromatographic techniques(GC), which is suitable for routine analysis of residual PETRA monomers in these hydrogels. Unreacted PETRA was initially identified using gas chromatography–mass spectrometry(GC–MS). The quantitation of analyte was performed and validated using gas chromatography equipped with a flame ionization detector(GC–FID). A linear relationship was obtained over the range of 0.0002%–0.0450%(m/m) with a correlation coefficient(r2)greater than 0.99. The recovery( 4 90%), intra-day precision(%RSD o 0.67), inter-day precision(%RSD o2.5%), and robustness(%RSD o1.62%) of the method were within the acceptable values. The limit of detection(LOD) and limit of quantitation(LOQ) were 0.0001%(m/m) and 0.0002%(m/m), respectively.This assay provides a simple and quick way of screening for residual acrylate monomer in hydrogels. 展开更多
关键词 Poly(ethylene oxide) (PEO) RESIDUAL MONOMER HydrogelGas chromatography–mass spectrometry (GC–MS) Gas chromatography–flame ionization detection (GC–FID)
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Capillary Electrochromatography Using C_8 Open Tubular Column Prepared by Sol-Gel Technique 被引量:1
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作者 李方 靳慧 +1 位作者 顾峻岭 傅若农 《Journal of Beijing Institute of Technology》 EI CAS 1996年第2期122-122,共1页
Open tubthar C8 columns were prepared by sol-gel technology and used in the electrochromatographic separations.
关键词 SOL-gel technology OPEN TUBULAR CAPILLARY COLUMN CAPILLARY ELECTROchromatography
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A novel profile modification HPF-Co gel satisfied with fractured low permeability reservoirs in high temperature and high salinity
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作者 Ya-Kai Li Ji-Rui Hou +6 位作者 Wei-Peng Wu Ming Qu Tuo Liang Wei-Xin Zhong Yu-Chen Wen Hai-Tong Sun Yi-Nuo Pan 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期683-693,共11页
Conformance control and water plugging are a widely used EOR method in mature oilfields.However,majority of conformance control and water plugging agents are unavoidable dehydrated situation in high-temperature and hi... Conformance control and water plugging are a widely used EOR method in mature oilfields.However,majority of conformance control and water plugging agents are unavoidable dehydrated situation in high-temperature and high-salinity low permeability reservoirs.Consequently,a novel conformance control system HPF-Co gel,based on high-temperature stabilizer(CoCl_(2)·H_(2)O,CCH)is developed.The HPF-Co bulk gel has better performances with high temperature(120℃)and high salinity(1×10^(5)mg/L).According to Sydansk coding system,the gel strength of HPF-Co with CCH is increased to code G.The dehydration rate of HPF-Co gel is 32.0%after aging for 150 d at 120℃,showing excellent thermal stability.The rheological properties of HPF gel and HPF-Co gel are also studied.The results show that the storage modulus(G′)of HPF-Co gel is always greater than that of HPF gel.The effect of CCH on the microstructure of the gel is studied.The results show that the HPF-Co gel with CCH has a denser gel network,and the diameter of the three-dimensional network skeleton is 1.5-3.5μm.After 90 d of aging,HPF-Co gel still has a good three-dimensional structure.Infrared spectroscopy results show that CCH forms coordination bonds with N and O atoms in the gel amide group,which can suppress the vibration of cross-linked sites and improve the stability at high temperature.Fractured core plugging test determines the optimized polymer gel injection strategy and injection velocity with HPF-Co bulk gel system,plugging rate exceeding 98%.Moreover,the results of subsequent waterflooding recovery can be improved by 17%. 展开更多
关键词 Low permeability reservoir High-temperature resistant gel Complexation reaction Polymer gel injection strategy Plugging rate Enhanced oil recovery
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Intelligent responsive self-assembled micro-nanocapsules:Used to delay gel gelation time
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作者 Chuan-Hong Kang Ji-Xiang Guo +1 位作者 Dong-Tao Fei Wyclif Kiyingi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2433-2443,共11页
In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can"go further"in the formation,but the most of the methods for delaying gel ... In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can"go further"in the formation,but the most of the methods for delaying gel gelation time are complicated or have low responsiveness.There is an urgent need for an effective method for delaying gel gelation time with intelligent response.Inspired by the slow-release effect of drug capsules,this paper uses the self-assembly effect of gas-phase hydrophobic SiO_(2) in aqueous solution as a capsule to prepare an intelligent responsive self-assembled micro-nanocapsules.The capsule slowly releases the cross-linking agent under the stimulation of external conditions such as temperature and pH value,thus delaying gel gelation time.When the pH value is 2 and the concentration of gas-phase hydrophobic SiO_(2) particles is 10%,the gelation time of the capsule gel system at 30,60,90,and 120℃is12.5,13.2,15.2,and 21.1 times longer than that of the gel system without containing capsule,respectively.Compared with other methods,the yield stress of the gel without containing capsules was 78 Pa,and the yield stress after the addition of capsules was 322 Pa.The intelligent responsive self-assembled micronanocapsules prepared by gas-phase hydrophobic silica nanoparticles can not only delay the gel gelation time,but also increase the gel strength.The slow release of cross-linking agent from capsule provides an effective method for prolongating the gelation time of polymer gels. 展开更多
关键词 Profile control and water shutoff Polymer gel Delayed gelation time Intelligent response SELF-ASSEMBLED Micro-nanocapsules
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Activation of endogenous neurogenesis and angiogenesis by basic fibroblast growth factor-chitosan gel in an adult rat model of ischemic stroke 被引量:6
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作者 Hongmei Duan Shulun Li +11 位作者 Peng Hao Fei Hao Wen Zhao Yudan Gao Hui Qiao Yiming Gu Yang Lv Xinjie Bao Kin Chiu Kwok-Fai So Zhaoyang Yang Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期409-415,共7页
Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactiv... Attempts have been made to use cell transplantation and biomaterials to promote cell proliferation,differentiation,migration,and survival,as well as angiogenesis,in the context of brain injury.However,whether bioactive materials can repair the damage caused by ischemic stroke by activating endogenous neurogenesis and angiogenesis is still unknown.In this study,we applied chitosan gel loaded with basic fibroblast growth factor to the stroke cavity 7 days after ischemic stroke in rats.The gel slowly released basic fibroblast growth factor,which improved the local microenvironment,activated endogenous neural stem/progenitor cells,and recruited these cells to migrate toward the penumbra and stroke cavity and subsequently differentiate into neurons,while enhancing angiogenesis in the penumbra and stroke cavity and ultimately leading to partial functional recovery.This study revealed the mechanism by which bioactive materials repair ischemic strokes,thus providing a new strategy for the clinical application of bioactive materials in the treatment of ischemic stroke. 展开更多
关键词 adult endogenous neurogenesis ANGIOGENESIS basic fibroblast growth factor-chitosan gel CHITOSAN functional recovery ischemic stroke neural stem cell newborn neuron
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Separation of Recombinant Geranylgeranyl Diphosphate Synthase of Deinococcus radiodurans from Expressed Strain Cell Homogenate by Immobilized Metal Affinity Chromatography on a Characterized Monolithic Cryogel Column
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作者 SHEN Shaochuan WANG Liangyan +5 位作者 SUN Zongtao LI Mingfeng LIU Chengzhi TIAN Bing YUN Junxian HUA Yuejin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第6期663-669,共7页
Geranylgeranyl diphosphate synthase (GGPPS) plays a key role in the biosynthesis of antioxidative carotenoid from the extremely radioresistant bacterium Deinococcus radiodurans. In this work, the recombinantGGPPS ex... Geranylgeranyl diphosphate synthase (GGPPS) plays a key role in the biosynthesis of antioxidative carotenoid from the extremely radioresistant bacterium Deinococcus radiodurans. In this work, the recombinantGGPPS expressed in Escherichia coli by cloning and transforming the gene dr1395 of D. radiodurans was isolated rapidly by an immobilized metal affinity supermacroporous cryogel, i.e., Cu2+-iminodiacetic acid (IDA)-cryogel. The properties of the Cu2+-IDA-cryogel were characterized using capillary-based mathematical model and experi- mental measurements. The obtained protein samples were analyzed by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The porosity of the present Cu2+-IDA-cryogel is 90.4% and the water permeability is 5.04x10-12 m2. From the capillary-based model, this cryogel presents a slightly wide normal pore (capillary) size distribution with the mean diameter of 55.2 μm, the standard deviation of 28.0 μm and the half of skeleton wall thickness of 2.8 μm. The pore size distribute from about 10 to 141 μm and the effective tortuosity of these capillary pores increases from 2.60 to 9.05. The isolation of the GGPPS from cell homogenate can be achieved at the flow velocity of 3.40x 10-4μm. s-1 by the Cu2+-IDA-cryogel bed. High-purity GGPPS (about 91.4%) is obtained according to the SDS-PAGE analysis of the elution samples, indicating that the present method is a promising, simple and ef- fective atmroach to isolate GGPPS from cell homoenate of engineering, strains. 展开更多
关键词 chromatography SEPARATION protein modeling bactenum
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Metal–Organic Gel Leading to Customized Magnetic‑Coupling Engineering in Carbon Aerogels for Excellent Radar Stealth and Thermal Insulation Performances 被引量:1
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作者 Xin Li Ruizhe Hu +7 位作者 Zhiqiang Xiong Dan Wang Zhixia Zhang Chongbo Liu Xiaojun Zeng Dezhi Chen Renchao Che Xuliang Nie 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期36-52,共17页
Metal–organic gel(MOG)derived composites are promising multi-functional materials due to their alterable composition,identifiable chemical homogeneity,tunable shape,and porous structure.Herein,stable metal–organic h... Metal–organic gel(MOG)derived composites are promising multi-functional materials due to their alterable composition,identifiable chemical homogeneity,tunable shape,and porous structure.Herein,stable metal–organic hydrogels are prepared by regulating the complexation effect,solution polarity and curing speed.Meanwhile,collagen peptide is used to facilitate the fabrication of a porous aerogel with excellent physical properties as well as the homogeneous dispersion of magnetic particles during calcination.Subsequently,two kinds of heterometallic magnetic coupling systems are obtained through the application of Kirkendall effect.FeCo/nitrogen-doped carbon(NC)aerogel demonstrates an ultra-strong microwave absorption of−85 dB at an ultra-low loading of 5%.After reducing the time taken by atom shifting,a FeCo/Fe3O4/NC aerogel containing virus-shaped particles is obtained,which achieves an ultra-broad absorption of 7.44 GHz at an ultra-thin thickness of 1.59 mm due to the coupling effect offered by dual-soft-magnetic particles.Furthermore,both aerogels show excellent thermal insulation property,and their outstanding radar stealth performances in J-20 aircraft are confirmed by computer simulation technology.The formation mechanism of MOG is also discussed along with the thermal insulation and electromagnetic wave absorption mechanism of the aerogels,which will enable the development and application of novel and lightweight stealth coatings. 展开更多
关键词 Metal-organic gels Heterometallic magnetic coupling Radar stealth Thermal insulation Computer simulation technology
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